Water hydrants in the northern climates are many times covered by a layer of snow, and thus are not readily locatable in the event that they are needed for a fire emergency or like happening, or they may be concealed in whole or in part by underbrush. The present invention provides a marking device adapted for ready attachment to a hydrant which will enable rapid location of the hydrant in the event that it is partially or completely concealed by snow, undergrowth or the like, and a device which can be collapsed or swung downwardly from its upright indicating position so that it will not present interference to the operation of the conventional operating nut on the hydrant. To applicant's knowledge there are no devices available of this nature for this purpose.